The present invention relates to an improvement of coupling structure for pipes of one of nonferrous metals including copper, stainless steel, aluminum, etc. to couple them to one another.
Generally, pipes of stainless steel, aluminum or another nonferrous metal are connected to one another with iron couplings(or connection structures), but the structure of the coupling has a fault that causes electrochemical corrosion of the pipes due to the contact between two different metals such as iron and a nonferrous metal.
Thus, to prevent the fault, couplings have come to be made of bronze or brass.
As stated above, the coupling of bronze or brass is certain to bring the anticorrosive nature to it, but the production cost makes it expensive for use and presents a fundamental fault.
Also, anticorrosive construction was proposed for a coupling to have a nonferrous metal, such as stainless steel, layer on the inner marginal edge of the iron coupling arranged to be in contact with the nonferrous metal pipe. However, this coupling is arranged to have the nonferrous metal layer directly in contact with the inner marginal edge of the iron coupling, such that, in the same way as stated before, electrochemical corrosion occurs in the nonferrous metal layer in contact with the iron coupling to subsequently corrode the nonferrous metal pipe in contact with the corroding nonferrous layer to a disadvantage.
The present invention is designed to provided an inexpensive but anticorrosive coupling structure for nonferrous metal piping, and its structure is constructed as follows.
1. A feature is that its structure comprises:
a two piece set of dually grooved iron socket component members having a first semicircular groove and a second semicircular groove both formed in the inner marginal wall face, the component members having the half shape of the socket component from division into halves of the socket along the axis of piping;
a separator unit, dually layered of a synthetic resin layer and a nonferrous metal layer, to fit in the first groove and itself also having a lengthwise groove;
a cylindrical packing formed to have at the ends sealing rings for fitting in the second grooves and to cover the inner surface of the two iron socket members in opposition; and
nonferrous metal pipes provided on the outer marginal edge with a stopper ring or lugs fitting into the first groove formed in the iron socket members, to be put together and tightened with bolts and nuts into an integral assembly in a manner that the nonferrous metal pipe ends are fitted in the sealing ring of the packing and the stopper ring or lugs on the pipes are fitted in the groove of the nonferrous metal layer of the separator.
2. Another feature is that the first semicircular grooves formed in the inner end walls of the two iron socket members receive the separator members of a resin layer and a nonferrous metal layer having at least a part of xe2x80x9cxe2x80x9d form or a similar form in section.
3. Still another feature is that the two iron socket members are formed into a xe2x80x9cTxe2x80x9d form pipe couple. A further feature is that the iron socket component connects with the non ferrous metal pipe in a way of not being in contact directly with each other.
To achieve the above features, the iron socket component is cut along the piping axis into halves whose inner faces are arranged to fittingly receive in their second grooves the sealing rings(3a) of the packing(3) and also receive in their first groove, positioned outer than the second groove, the separator of a resin layer and a nonferrous metal layer to couple through the separator placed in-between with a nonferrous pipe, such that, despite the fact that a nonferrous metal pipe is connected to an iron socket component without a direct contact between them, a good sealing state is still kept for coupling with pipes not to slip off for separation.
Thus, the iron socket component unit and the nonferrous metal pipe are not to be in contact with each other in connection so that the electrochemical corrosion to occur in the conventional coupling is not to happen in the coupling of the invention.